I am trying to use system command to perform a particular task on a group of input files; When I provide the file nales one by one my code works but if I want to provide the file names as a vector it fails.

@resultad is a vector containg filepath/name. Do you know what the problem is please? I checked the code Perl_XMLparsing.pl and I am sure it does not recieve the files (@resultad) ...

You show a part of your program, but you don't show that part where the error occurs. From the message, I would guess that XML::Simple is complaining about an incorrect XML file, so maybe you should have a look at this file using a hex editor.